The advent of vertical and horizontal louver type blinds has brought about new concepts in interior design in commercial and residential installations. Vertical louver type venetian blind systems have been particularly well received in contemporary architecture where relatively large expanses of window glass are employed or large room partitions are desired. The vertical louver blind may be of substantial vertical height and, when closed, may extend along a considerable horizontal length to cover a wall, a window, or to partition a room.
Conventional louvers, also called slats or vanes, of a vertical blind are adapted for lateral movement between an open blind position, when the blind is drawn to one or opposite ends of a support track or channel adjacent their tops, and a closed position, when the louvers are positioned in generally equal spaced relation to one another along the length of the support track or channel. The louvers are also adapted for selective rotation about their longitudinal axes between open and closed positions when in the closed blind position, to control the amount of light entering between the louvers into or out of the adjacent room.
The vertical louvers may be made of vinyl or other suitable material, colored to add an accent color to the room or colored to blend with the primary color of the room. The louvers may also be made or covered with a fabric material to achieve a specific design effect. For example, U.S. Pat. No. 4,049,038 issued to Hyman, Cayton and Rosenquist and assigned to LOUVERDRAPE, INC. discloses a functional and decorative covering material, such as wallpaper or reflective materials, for louvers, where the materials are held from sliding longitudinally along each louver at a single attachment point. A backing material of rigid construction, e.g., heavy grade paper or cardboard, is attached to the covering material and placed in interlocking relationship with opposed inwardly projecting, longitudinal louver flanges. A single spot of glue may then be used to keep the composite cover with backing attached to the slat.
This louver system enables one to easily customize and change the covering materials on the louvers. The assembly of a complete louver system is fabricated after the louvers are individually covered with the desired functional or decorative covering material involved.
To improve the system, save money on materials, and give the louvers a more finished look, it is desirous to attach the cover directly on each louver. Unfortunately, because two different materials are used to make the louvers, that being for the cover and the slat, and because during the construction and use of the louvers they are exposed to a wide range of temperatures and humidities, the cover and slats can expand and contract at different rates, causing distortion and wrinkling if the coefficient of expansion thereof are too dissimilar. Accordingly, there is a need for an aesthetically pleasing louver with the cover attached directly to each louver slat wherein the covered louver can withstand fluctuations in temperature and humidity without distortion or wrinkling and without the need to match the coefficient of expansion of the louver slat and cover materials.